Coupling device and medical line set including same

ABSTRACT

The present invention refers to a medical line set ( 10 ) having a breakable coupling device ( 90 ), and to such a coupling device ( 90 ). More particularly the present invention refers to an medical dialysis line set ( 10 ), such as a peritoneal dialysis (PD) line set, including a liquid introducing portion ( 20 ), a liquid distribution portion or PD portion ( 40 ) and a drain portion ( 80 ), for introducing and extracting dialysis liquid from a patient, the line set particularly including said coupling device ( 90 ) for connecting and disconnecting the liquid introducing portion ( 20 ) in order to introduce and extract spent medical solution.

TECHNICAL FIELD

The present invention refers generally to the medical field andspecifically to the field of dialysis, such as peritoneal dialysis (PD).More particularly the present invention refers to a medical line set andto a breakable coupling device to be used in such a medical line set.The medical line set may be a peritoneal dialysis line set (PD lineset), including a liquid introducing portion connectable with medicalsupply bags for holding medical solutions, a liquid distribution portion(PD portion) and a drain portion for extracting the solutions, the lineset particularly including said coupling device for connecting anddisconnecting the liquid introducing portion for introducing andextracting spent medical solution.

BACKGROUND OF THE INVENTION

Dialysis is widely used within medical therapy in the treatment ofvarious diseases and disorders. One example is dialysis in the treatmentof patients suffering from different stages of acute and chronic renaldiseases. These patients are generally treated either by haemodialysis(HD) or peritoneal dialysis (PD). During HD the metabolic waste productsare cleared by means of an artificial membrane outside the body, whereasduring PD the waste products are cleared by means of a biologicalmembrane, such as the peritoneum or peritoneal membrane. There are bothmanual and automated modes of PD and to find the right treatment modefor each patient, medical, social and economical aspects have to beconsidered.

Continuous Ambulatory Peritoneal Dialysis (CAPD) is a frequently usedform of PD. It is a manual method where each exchange is taken care ofby the patient himself. To increase the efficiency of CAPD and to helpthe patient with the exchanges, a machine (e.g. a PD cycler) can beused. A PD cycler is a machine that automatically administers allexchanges of PD solutions according to a predetermined schedule. Thereare different PD applications when using a machine, all summarised withthe term APD, Automated Peritoneal Dialysis.

In the different modes of PD, especially in an APD assembly, a connectoris often used to detach a multi-divider tubing system of the PD medicalassembly, including the empty PD bags from the PD portion, in order totransfer the empty medical supply bags to the drain portion fordischarge of spent PD solution during the following treatment. This isto assist the patient in the situation where there is no sink or thelike available for discharge of spent PD solution during the treatment.

Presently known is an APD system including a standard luer lockconnection having a female connecting part and a male connecting partfor connecting the liquid introducing portion to the PD portion. Theconnection is mounted before sterilisation of the whole assembly. Aftersterilisation and completion of the dialysis procedure the connection isunscrewed and the liquid introducing portion is connected to the drainportion of the next PD medical assembly.

One major disadvantage with said connection is that the connector tendsto get loose during sterilisation as well as during storage and airmaybe sucked into or leak into the tubing system of the assembly. Air inthe system may cause pain to the patient and may even be fatal.Moreover, a loose-fitting connector provides a potential for bacterialcontamination of the line set, which in turn may result in seriousinflammation of the peritoneum of the patient.

A further disadvantage with the above construction is, due to theconstruction of the distinct elements forming the connector ends, thateach connector end is required to be manufactured separately, which istime-consuming and increases costs.

SUMMERY OF THE INVENTION

It is towards the need for an improved medical assembly with a safe andsimple construction which may be sterilised and stored without the riskof air leakage or bacterial contamination, that the present invention isdirected.

Thus, one object of the invention is to provide a medical line set,including a coupling device, which is safe as regards the risk of airleakage or bacterial contamination after sterilisation and duringstorage.

One further object is to provide an improved coupling device for saidmedical line set which has a simple construction resulting in a lowmanufacturing cost.

In order to fulfil the above objects the present invention provides amedical line set having a liquid introducing portion with at least onefirst connector, a liquid distribution portion with a second connectorand a drain portion with a third connector, the line set furthercomprising a coupling device for connecting the liquid introducingportion to the liquid distribution portion, said coupling device having

-   -   a first connecting part connectable with the liquid distribution        portion;    -   a central part;    -   a second connecting part connectable with the liquid introducing        portion, the central part and the second connecting part being        integrally formed with the first connecting part; and    -   a predetermined breaking section between the central part and        the first connecting part.

In one aspect of the invention the medical line set is a PD line set andin a preferred aspect it is an APD line set.

According to the present invention there is also provided a couplingdevice, which is particularly useful in a medical dialysis line sethaving a liquid introducing portion with at least one first connector, aliquid distribution portion with a second connector and a drain portionwith a third connector for connecting the liquid introducing portion tothe liquid distribution portion, said coupling device comprising

-   -   a first connecting part connectable with the liquid distribution        portion;    -   a central part;    -   a second connecting part connectable with the liquid introducing        portion, the central part and the second connecting part being        integrally formed with the first connecting part; and    -   a predetermined breaking section between the central part and        the first connecting part.

In a preferred embodiment the central part of the coupling device ofsaid medical line set is adapted to be connectable with the thirdconnector.

In a further preferred embodiment the predetermined breaking section ofthe coupling device of said medical line set is defined by a groove inthe junction between the central part and the first connecting part andis breakable at finger pressure.

In one aspect the coupling device is adapted to be used in a PD line setand in a preferred aspect it is adapted to be used in an APD line set.

Moreover, the present invention provides a method for performingdialysis in a medical line set having a liquid introducing portion withat least one first connector, a liquid distribution portion with asecond connector and a drain portion with a third connector, the lineset further comprising a coupling device for connecting the liquidintroducing portion to the liquid distribution portion.

According to a preferred aspect the method refers to a method ofperforming dialysis in an PD line set and more preferably in an APD lineset.

By means of the present invention the risk for patients on dialysis tobe harmed due to air leakage into the system or bacterial contaminationthereof is minimised. A further benefit provided by the presentinvention is that the coupling device is easy to produce and easy tomount, which makes the coupling device, as well as the medical line setincluding the coupling device, safe and economical. Moreover, bymanufacturing the coupling device as an integrated moulded product, thecost of manufacturing the PD tubing set is decreased.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a medical line set according to thepresent invention including a coupling device according to theinvention;

FIG. 2 is a front view of a coupling device according to the presentinvention; and

FIG. 3 is a cross sectional view of a coupling device according to thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

The medical line set according to the invention has a liquid introducingportion, a liquid distribution portion, a drain portion and a couplingdevice for connecting the liquid introducing portion to the liquiddistribution portion.

The medical line set of the invention is preferably a medical dialysisline set, such as a PD line set and more particularly an APD line set.

Referring to FIG. 1 one embodiment of a medical line set according tothe present invention is shown. The medical line set 10 is a medicalline set for APD. The APD line set 10 includes a liquid introducingportion 20, a liquid distribution portion or PD portion 40, a drainportion 80 and a coupling device 90. According to the embodiment shownin FIG. 1 the coupling device 90 is placed between the liquidintroducing portion 20 and the liquid distribution portion 40. Thecoupling device 90 has a first connecting part 92, a second connectingpart 94 and a central part 96. The first connecting part 92 of thecoupling device 90 is connected to the liquid distribution portion 40and the second connecting part 94 of the coupling device 90 is connectedto the liquid introducing portion 20.

The liquid introducing portion 20 includes connection tubes 22 withclamps 26 a and one or more first connectors 24 adapted for theintroduction of different medical solutions from medical supply bags(not shown). The liquid introducing portion 20 further includes adistributor 28 and a first feed line 30 for delivering the medicalsolutions to the liquid distribution portion 40.

The liquid distribution portion 40 includes according to the embodimentshown in FIG. 1 a heater bag 54 and a drain bag 56. The heater bag 54 isused for the medical solution, e.g. a PD solution, to be preheated,weighted and introduced into the patient and the drain bag 56 isintended for the spent PD solution being extracted from the patientafter the peritoneal dialysis is finished.

In connection with the heater bag 54 there is provided a second feedline 42, a dose valve 46, a first F-connector 44, a third feed line 50provided with a clamp 26 b and a first seal 52 a for introducing medicalsolutions from the liquid introducing portion 20 to the heater bag 54.Liquid from the heater bag 54 flows into a patient via an inflow valve48, an inflow line 58, a Y-connector 62, a patient line 64 provided witha clamp 26 d and an injection port 68, and a second connector 66attached to a PD catheter (not shown) entered into the peritoneal cavityof the patient.

In connection with the drain bag 56 of the liquid distribution portion40 there is provided a second seal 52 b, a first drain line 74, a secondF-connector 72, a sampling port 76 and an outflow line 60 having anoutflow valve 70 for allowing liquid to flow, on one hand, from thepatient to the drain bag 56 and, on the other hand, from the drain bag56 to the drain portion 80.

The drain portion 80 of the medical line set 10 includes a second drainline 84, having a drain valve 82 and a clamp 26 c, and a third connector86. Said third connector 86 is adapted to be connectable with thecoupling device 90 for discharge of used PD solution.

According to a preferred embodiment the coupling device 90 and the thirdconnector 86 are both standard luer lock or luer cone connectors.

The present invention also refers to a coupling device which may be usedin a medical line set as described above.

Referring now to FIGS. 2 and 3 there is shown one embodiment of acoupling device according to the invention. The coupling device 90 has afirst connecting part 92, a central part 96 and a second connecting part94. These three parts 92, 96 and 94 are all cylindrically shaped tubularparts and are formed in one piece.

The central part 96 is provided with a predetermined breaking section100 defined by a circumferential groove in the junction between thecentral part 96 and the first connecting part 92. The coupling device 90is adapted to be broken along this predetermined breaking section 100into two pieces. The thickness of the material of the breaking section100 is such that the breaking section 100 may be broken when either ofthe first connecting part 92 and the second connecting part 94 istwisted or bent. The breaking section 100 is breakable at fingerpressure.

Furthermore, the central part 96 of the coupling device 90 is preferablyprovided with threads 98 along the whole or part of its length. Withreference to FIG. 2 a coupling device 90 is shown wherein the centralpart 96 is provided with threads 98 along part of its length, i.e. thepart close to the breaking section. In order to facilitate themanufacturing of the coupling device 90 as an integral piece the threads98 of the central part may, as shown in FIG. 2, be divided into twoparts along the circumference of the central part 96. As appears fromFIG. 2 part of the threads may be bevelled resulting in bevelledsurfaces 102. Alternatively, the threads may be distinctly divided intotwo or more groups.

In the embodiment shown in FIGS. 2 and 3, the central part 96 is shapedin the form of a male luer cone having standard luer cone dimensions.Said standard dimensions of a male luer cone connector is as follows:the connection diameter is 4.29 mm and the length of the cone is atleast 7.5 mm with a cone angle of 1°43′6″ towards the smallest diameterof the luer cone. The connection diameter of the luer cone is, withreference to FIG. 2, the diameter adjacent the first connecting part 92at the predetermined breaking section 100 and the smallest diameter ofthe luer cone is the one adjacent the second connecting part 94.

The second connecting part 94 is preferably provided with two or moregripping surfaces 104 for twisting said second connecting part 94 aroundits axis with the fingers in order to separate the second connectingpart 94 and the central part 96 from the first connecting part 92. Thesecond connecting part 94 of the coupling device 90 shown in FIG. 2 isprovided with four gripping surfaces regularly arranged around saidsecond connecting part 94. While any number of gripping surfaces may beprovided, the number is suitably at least two.

Preferably the coupling device has the form of a luer lock connector,the central part thereof having the form of a male luer cone.

According to another embodiment the luer cone luer lock connector may bepresented without threads, the central part having the form of a maleluer cone adapted to be pressed into a mating female luer connector.

Moreover, the present coupling device may have any suitable dimensionsas long as it is adapted to be coupled to a mating connector, shown asthe third connector 86 in FIG. 1. The central part 96 may e.g. vary inlength.

Breaking the present coupling device 90 along the predetermined breakingsection 100 results in two pieces, one piece comprising the threadedpart or the cone formed part to be the drain portion, i.e. the centralpart 96 and the second connecting part 94, and connected to the otherpiece comprising the first connecting part 92.

The coupling device of the present invention is produced in one piecethrough any suitable known technique, such as injection moulding andform pressing. The coupling device may be made of any suitable material,e.g. thermoplastic polymers, such as polyvinyl chloride, polystyrene andpolyurethane, or combinations thereof.

According to a preferred embodiment the coupling device according to theinvention is made of polyvinyl chloride by injection moulding understandard process conditions well known within the art.

The method for performing dialysis in a dialysis line set according tothe present invention is described with reference to FIG. 1. It impliesthe use of a medical line set 10 having a liquid introducing portion 20with at least one first connector 24, a liquid distribution portion orPD portion 40 with a heater bag 54, a drain bag 56 and a secondconnector 66, and a drain portion 80 with a third connector 86, the lineset further comprising a coupling device 90 having a first connectingpart 92 connectable with the liquid distribution portion 40; a centralpart 96 adapted to be connected with the third connector 86; a secondconnecting part 94 connectable with the liquid introducing portion 20,the central part 96 and the second connecting part 94 being integrallyformed with the first connecting part 92; and a predetermined breakingsection 100 defined by a groove in the junction between the central part96 and the first connecting part 92 and being breakable at fingerpressure. Said method comprises the steps of

-   -   introducing a PD solution via the liquid introducing portion 20        into the heater bag 54 to prepare a predetermined dose of the PD        solution;    -   introducing said dose of PD solution into the peritoneal cavity        of a patient;    -   allowing the predetermined dose of PD solution to reside in the        peritoneal cavity of the patient for a predetermined dwell        period;    -   extracting the used PD solution from peritoneal cavity of the        patient and allowing said used solution to enter the drain bag        56;    -   separating the liquid introducing portion 20 from the liquid        distribution portion 40 through breaking the predetermined        breaking section 100, thus separating the central part 96 and        the second connecting part 94 of the coupling device from the        first connecting part 92; and    -   connecting the central part 96 and the second connecting part 94        to the third connector 86 of the drain portion 80 for draining        the used PD solution via the drain portion 80 to the medical        supply bags (not shown).

The coupling device and the medical line set of the invention ispreferably used in an APD system, but may also be used in other systems,having the need for a coupling device according to the invention.

The function of a medical line set according to the invention will nowbe described with reference to the embodiment shown in FIG. 1, whereinthe medical line set is an APD medical line set.

First a sterile medical line set 10 is mounted on a PD cycler (notshown). The PD cycler includes four valves, dose valve 46, inflow valve48, outflow valve 70 and drain valve 82, which are all initially closed.The liquid flow on the PD cycler can be created optional, by e.g.gravitation, in a pressure chamber, with a pump etc. Clamps 26 a, b, c,d of the PD medical line set 10 shall now be closed. The firstconnectors 24, which maybe screw connectors, piercing connectors etc.,are attached to medical supply bags (not shown) including for thetreatment required solutions. The liquid introducing portion of amedical PD line set used in a previous treatment (not shown) is attachedto the third connector 86 of the drain portion 80. Now the clamps 26 aare opened and the PD medical line set is automatically primed with PDsolution. The dose valve 46 of the PD cycler and clamp 26 b are openedand liquid from the medical supply bags flows through first and secondfeed lines 30 and 42 via the first F-connector 44 and the third feedline 50 to the heater bag 54 to prepare a required and predetermineddose of a PD solution. When the required dose has been filled into theheater bag 54 the dose valve 46 is closed. In the meantime the secondconnector 66 is connected to a PD catheter (not shown) of a patient tobe treated. The PD solution in the heater bag 54 is heated to aroundbody temperature and weighed a first time to define a first weight. Theinflow valve 48 and the clamp 26 d are opened and the PD solution isallowed to flow through the inflow line 58 and the patient line 64 intothe peritoneal cavity of the patient via the second connector 66 and thePD catheter of the patient. When the required dose of PD solution hasbeen distributed to the patient the inflow valve 48 is closed. Theinjection port 68 on the patient line 64 may be used for injecting intothe patient any further solution, substance, etc. such as insulin andantibiotics. Alternatively, it may be used for taking samples, such assamples of the spent PD solution.

After a predetermined dwell period, i.e. the time during which the PDsolution is residing in the peritoneal cavity without being administeredor drained and during which time the dialysis exchange is taking place,the outflow valve 70 is opened and the spent PD solution is allowed toenter the drain bag 56 through patient line 64, outflow line 60, secondF-connector 72 and first drain line 74. The outflow valve 70 is closed,the spent PD solution, now in the drain bag 56, is weighed a second timeto define a second weight. Said second weight is compared to the firstweight of the heater bag 54 and the difference between the two weightsis calculated for monitoring and controlling the treatment. The samplingport 76 may be used for taking samples of the spent PD solution.

Finally, the drain valve 82 and the clamp 26 c are opened and the spentand weighed PD solution is drained through the second drain line 84 intothe empty medical supply bags used in a previous treatment and attachedvia the third connector 86. After completion of a treatment the liquidintroduction portion 20 of the medical PD line set used in the previoustreatment is disconnected from the third connector 86 of the drainportion 80 and discarded. In this final step the coupling device 90 ofthe now used medical line set (10) is separated into two pieces, onepiece comprising the first connecting part 92 and the other piececomprising the second connecting part 94 and the central part 96, bybreaking the predetermined breaking section 100 through twisting orbending either of the connecting parts. The resulting second connectingpart 94 together with the central part 96 having the shape of a luerlock is then connected to the mating third connector 86, which has theform of a mating luer lock. In general the patient does not separate thecoupling device into two pieces, thus moving the liquid introducingportion to the drain portion, until just before the next treatment.

The medical line set including the coupling device according to theinvention may, if needed and suitable, include two or more of saidcoupling devices.

One example of liquid used in the medical line set according to theinvention is a PD solution and it may be any PD solution known in theart.

The integrally formed coupling device of the invention is easy, safe andeconomic to manufacture. Moreover, mounting of the coupling device iseasy and safe. Being formed in one piece the coupling device is safefrom air-leakage and bacterial contamination after sterilisation andduring storage.

A preferred embodiment of the invention has been described. However,many variations of the invention, which are within the spirit and scopeof the invention as claimed in the following claims, may be made.

Reference numerals:  10 medical line set  20 liquid introducing portion 22 connection tube  24 first connector  26a, b, c, d clamp  28distributor  30 feed line, first  40 liquid distribution portion/PDportion  42 second feed line  44 first F-connector  46 dose valve  48inflow valve  50 third feed line  52a, b seal  54 heater bag  56 drainbag  58 inflow line  60 outflow line  62 Y-connector  64 patient line 66 second connector  68 Injection port  70 outflow valve  72 secondF-connector  74 first drain line  76 sampling port  80 drain portion  82drain valve  84 second drain line  86 third connector  90 couplingdevice  92 first connecting part  94 second connecting part  96 centralpart  98 thread 100 predetermined breaking section 102 bevelled surface104 gripping surface

1. A method for performing peritoneal dialysis with a medical line sethaving a liquid introducing portion with at least one first connector, aliquid distribution portion or PD portion with a second connector, and adrain portion with a third connector, the line set further comprising acoupling device for connecting the liquid introducing portion to theliquid distribution portion, said coupling device having: a firstconnecting part connectable with the liquid distribution portion; acentral part; a second connecting part connectable with the liquidintroducing portion, the central part and the second connecting partbeing integrally formed with the first connecting part; and apredetermined breaking section between the central part and the firstconnecting part, the method comprising the steps of: introducing amedical solution via the liquid introducing portion into a heater bag toprepare a predetermined dose of a peritoneal dialysis (PD) solution;introducing said predetermined dose of PD solution into the peritonealcavity of a patient; allowing the predetermined dose of PD solution toreside in the peritoneal cavity of the patient for a predetermined dwellperiod; extracting the used PD solution from peritoneal cavity of thepatient and allowing said used solution to enter the drain bag;separating the liquid introducing portion from the liquid distributionportion through breaking the predetermined breaking section, thusseparating the central part and the second connecting part of thecoupling device from the first connecting part; and connecting thecentral part and the second connecting part to the third connector ofthe drain portion for draining the used PD solution via the drainportion.
 2. The method according to claim 1, wherein the line set is aperitoneal dialysis line set.
 3. The method according to claim 2,wherein the line set is an automated peritoneal dialysis line set. 4.The method according to any one of claims 1-3, wherein the central partof the coupling device has the shape of a luer lock connector.